By Laila Bassam

BEIRUT, May 11 (Reuters) - Lebanese troops patrolled Beirut on Sunday after Hezbollah fighters pulled back from areas they had seized in deadly gunbattles with supporters of the U.S.-backed government.

Hezbollah, a political group backed by Iran and Syria that has a guerrilla army, said on Saturday it was ending its armed presence in the capital after the army -- seen as a neutral player -- overturned government measures against the group.

In the worst internal fighting since Lebanon's 1975-90 civil war, Hezbollah had taken over much of Beirut after its fighters routed gunmen loyal to the anti-Damascus governing coalition.

The four days of fighting, in which 37 people were killed, erupted after the government said it was taking action against Hezbollah's military communications network and sacked the head of security at Beirut airport, who was close to the group.

Hundreds of troops backed by armoured vehicles set up roadblocks and took up positions on streets in the mainly Muslim part of the capital.

There were no gunmen in sight but youths maintained barricades on some major roads that kept Beirut's air and sea ports closed.

While calm was restored in Beirut, clashes raged overnight in the northern city of Tripoli, Lebanon's second-largest, between pro- and anti-government gunmen.

Security sources said there had been a number of casualties but had no details.

Political deadlock has gripped Lebanon for 18 months over opposition demands for a greater say in government.

AlertNet news is provided by